1. Field of the Invention
The present invention relates to a guidebar shogging guide apparatus for warp knitting machines and in particular to a guide apparatus that is adjustable and automatically programmable in fixed increments that are proportional to the knitting machine needle spacing.
2. Discussion of the Relevant Art
Shogging mechanisms of different types are available in the art and are disclosed in a textbook entitled, "Warp Knitting Technology" by D. F. Paling first published in 1952 and reprinted in 1970 by the Columbine Press (Publishers Limited). Another shogging or steering element is disclosed in "Die Kettenwirk Maschine" by Emil Michael, published by Konradinverlagrobert Kohlhammer of Stuttgart, West Germany. Pages 37 through 40 disclose a guide mechanism to control the movement of a warp knitting machine guidebar which contain seven setting elements (see FIG. 55 at page 39) to obtain the incremental distances that the guidebar is to be moved. The movable setting elements are placed into position by means of a conventional jacquard arrangement. The jacquard arrangement moves the setting element into a predetermined position so that the head portion of the setting element provides a defined thickness along a longitudinal axis. By choosing a combination of different setting elements, having different thicknesses, the longitudinal thickness which determines the position of the slider bar that is operably coupled to the guidebar may be modified in accordance with the preset program. In the embodiment disclosed, the first setting element always remains in position and is provided with a stepped portion. The stepped portion is equivalent to one unit of displacement with a spacing between the needles on the needle bar. In its thinner portion, it is made to correspond to the known setting of the slider which is coupled to the guidebar. The other setting elements are brought into the path of the slider when they are activated by the jacquard mechanism and thus provide the additional longitudinal thickness and longitudinal displacement for the slider bar. The second setting element is provided with a thickness equal to two units and the third and remaining elements are each provided with a thickness in the longitudinal direction equivalent to four units of displacement. The step provided by the thickness of four units of displacement is sufficiently large so that during the activation of the third setting element the second setting element is completely enfolded when it is not activated. When a warp knitting machine is provided with a large needle separation on the needle bar then the size of each unit of displacement is thick enough so that the thickness of the setting elements are sufficiently thick in the longitudinal direction to be rugged and have a long life. If the needle spacing or separation therebetween on the needle bar is to be very small then it is necessary to utilize very thin setting elements which have the disadvantage of minimal strength during the strain placed upon it when the machine is operated. The necessity for maintaining the setting elements to their prescribed thicknesses is obvious, since the movement of the guidebar must be sufficient to clear a prescribed number of needles to perform with the design program. If the thickness of the setting elements change with time, since they may wear, the shogging of the guidebar may not be sufficient to clear the required needle thereby causing defects in the material manufactured. With the devices known, every time the needle spacing is varied, the thickness of the setting elements must be changed to correspond thereto in order to provide the proper increments of deflection for the guidebar.
The present invention overcomes the shortcomings found in the prior art by providing a guide apparatus similar in function to the above-described type wherein the setting elements are always of a sufficient thickness and stability to be reliable and have minimal wear. This is accomplished by providing setting elements which are thicker than the known units and instead of providing a raised portion to obtain the incremental displacement units a stepped down or depression is utilized to obtain the change in incremental distance. Furthermore, the incremental distance is made proportional to the needle spacing and not directly equal thereto. A means for converting the incremental change in thickness of the actual needle spacing is provided by a unique shogging lever operatively coupled to the slider bar associated with the guide apparatus.